When the U.S. Food and Drug Administration reclassified eggs as a "potentially hazardous food" in 1990, producers initially recoiled at the news but then welcomed the change.

The move meant public food operations must store, handle and prepare eggs with the same attention to proper cooking times and refrigeration temperatures as any raw animal food.

The change in the status of eggs became necessary to combat the increasing problem of Salmonella enteriditis, a harmful bacteria that is estimated to infect one egg per 10,000.

"We do not have sterile food," said Cathy McCharen, director of the Egg Nutrition Center in Washington. "We all eat bacteria daily in small amounts. The idea in food service (and home kitchens) is to prevent bacterial growth, not eliminate it. No food that is brought into the kitchen is sterile."

In a recent report, the Centers for Disease Control described how easily raw or undercooked eggs can cause illness. In one case, homemade banana pudding with meringue topping infected all six people who were served the dessert, with three requiring hospitalization. Health officials believe the pudding and meringue were undercooked and then improperly stored during transit.

Another episode occurred at a restaurant brunch for a wedding party. Of the 45 persons who ate eggs Benedict with Hollandaise sauce, 38 (84%) became ill. Again, the eggs were mishandled. Investigators found that the eggs used in the Hollandaise were pooled, allowing contaminated eggs to come in contact with clean ones. Then the sauce was incompletely cooked and served more than one hour after it was prepared.

The FDA has issued guidelines for proper egg handling to prevent such incidents. These include:

* Lightly cooked foods containing eggs, such as soft custards and French toast, may be risky for those in high-risk groups such as infants, the elderly, pregnant women and immuno-compromised individuals.

* Cook eggs thoroughly until both the yolk and white are firm, not runny. Recommended cooking times are five minutes for poached; one minute at 250 degrees for scrambled; seven minutes at 250 degrees for sunny side; and seven minutes in boiling water for boiled.

* Wash hands with hot, soapy water before and after they come in contact with eggs and uncooked egg-rich foods. The same applies to utensils, equipment such as blenders and work areas.

* Use only Grade A or better eggs. Avoid eggs that are cracked or leaking.

* Discard the egg if any shell falls into the egg.

* Leave eggs in their original carton and store them in the main section of the refrigerator, not in the egg section in the door--the temperature in the door is higher.

* Never leave eggs or egg-containing foods at room temperature for more than two hours, including preparation and serving (but excluding cooking) times.

* When refrigerating a large amount of a hot egg-rich dish or leftover, divide it into several small, shallow containers so it will cool quickly.

* Cook scrambled eggs in batches no larger than three quarts. Hold for serving at 140 degrees or hotter, such as on a steam table. Do not add a batch of just-cooked scrambled eggs to leftover eggs held on a steam table.